Industrial chicken production is an enormous business reaching a volume of around 6.7 tons in 2007. Optimal feeding of the chickens is an important factor in the process of producing chickens.
The reference book “Commercial Poultry Nutrition” (3rd edition, 2005, ISBN 0-9695600-5-2) is a standard textbook [1] relating to the area of nutritional aspects of chicken production. Below is a summary considered relevant as a background for the present invention.
Diets for chicken are typically referred to as “starter diets” and “grower diets”. The major ingredients delivering energy in diets are corn, soybean, soy oil and amino acids. Corn is a major contributor of metabolizable energy. The starch of the endosperm, which is mainly composed of amylopectin, and the germ which is mostly oil constitute the energy value of corn. Typical energy values of corn alone expressed in kcal/kg at 85% dry matter are ranging from 3014 to 3313 (page 12 [1]). Energy levels of starter and grower diets are typically in the range of 3000 to 3100 Kcal/kg. In many countries wheat is also commonly used in poultry diets. Such diets have similar energy levels as mentioned above. As a protein source soybean has become the worldwide standard against which other protein sources are compared. Its amino acid profile is excellent for most types of poultry, and when combined with corn or sorghum, methionine is usually the only factor in inadequate amounts. Additionally, fats and oils provide a concentrated source of energy in the diets and even relatively small changes in levels can have significant effects on diet ME. Finally, the diet is supplemented with synthetic amino acids such as methionine and lysine. Other important sources used are barley, sorghum and other cereals, and byproducts contributing to energy.
With respect to production cost, metabolizable energy (ME) is the most costly nutrient in an ingredient or diet [5]. The determination of metabolizable energy is derived by extrapolation to 100% inclusion from a regression equation relating test diet ME values to proportion of test ingredient in such diets. Feed is assayed for gross energy and nitrogen, and excreta is dried and likewise assayed. All analytical data is usually expressed on a moisture free basis. Reference [5] describes this precisely with examples of such calculations to obtain the final ME value.
The standard recommended metabolizable energy level for chicken feed is well established in the art and chicken producers use such a feed product in order to ensure optimal growth of the chickens. At the filing date of the present application, a chicken producer would generally not use a feed with less than the standard recommended metabolizable energy level as such a feed would result in insufficient growth of the chickens or the chickens would eat far too much feed.
At the filing date of the present application the standard used metabolizable energy level for chicken feed is shown in table 5.12, page 243 of the reference book [1]. The herein most relevant data of this table 5.12 are:
StarterGrowerHubbardRossCobbHubbardRossCobbME300030403023308031403166(kcal/kg)
Hubbard, Ross and Cobb are names of the most commonly used chicken breeds for broiler chicken production.
GalliPro® (Chr. Hansen) is a commercial Bacillus subtilis product used in chicken production. This product is a probiotic and as discussed in the reference textbook [1] (page 91-92) such a product is known to be used as a probiotic in chicken production. The reference book [1] describes two major types of probiotic products: viable microbial cultures and microbial fermentation products. Most research has been centered on Lactobacilli, Bacillus subtilis and some Streptococcus species. It has been suggested that use of probiotics result in a) beneficial change in gut flora with reduction in population of E. Coli; b) lactate production with subsequent change in intestinal pH; c) production of bacteriocins substances and d) reduction of toxin release.
Yeast has been used in animal feed and the human food industry for many years. A Bulgarian article [2] mentions the use of Saccharomyces cerevisiae and adding of this yeast to diet. Adding BioPro-I (comprising yeast) to the combined forage led to the improvement of forage protein, and adding 0.1% S. cerevisiae led to improved utilization of the energy in the forage compared to the group without any probiotic additive. The data in the article [2] shows increasing body weight using standard optimal diets (starter and finisher).
The textbook [1] and this article [2] do not describe using probiotics such as Bacillus species to improve utilization of the metabolizable feed energy.
Commercial marketing material information relating to Chr. Hansen's product, GalliPro® can be found in an article by Nelson Carvalho [3] entitled “Prospects for probiotics in broilers” on the Internet.
The Nelson Carvalho article [3] indicates that there may be some improvement of the chicken body weight increase by using GalliPro® in connection with an unspecified chicken feed product. In relation to the chicken feed product the article simply mentions “under commercial-type conditions”. The Nelson Carvalho article does not describe anything with respect to a possible GalliPro® related improvement of utilization of the metabolizable feed energy. The article describes the advantages of using probiotics with the purpose of replacing the use of antibiotics, as also described in the textbook [2]. Objectively, the skilled person would understand that the unspecified chicken feed products mentioned in the Nelson Carvalho article [3] would be a feed product with a standard metabolizable energy level as discussed above (i.e. 100% ME)